Accurate measurement of thermal transmittance

Multiple heat flux plates and temperature sensors

The system includes two Hukseflux HFP-01 heat flux plates allowing you to measure two locations or building elements simultaneously. 10m long cables allow easy routing of external temperature sensors to outside.

Illustration of heat loss and U-value measurement

ISO 9869 U-value measurement process

  1. Install sensors and data logger

    With everything enclosed in a protective case, the U-value Measurement System is easy to transport to the site.

    Installation requires that heat flux plates and temperature sensors are temporarily affixed to the building element being measured.

    Once configured, the data logger will take readings every few minutes and store them for later data analysis.

    Person carrying U-value kit
    Heat flux plate and temperature sensors on a wall
  2. Leave running for minimum 72 hours

    Once configured, the U-value measurement system must be left in place for a minimum of 72 hours to record readings of internal temperature and heat flux at regular intervals.

    All data is stored on the integrated data logger and can be accessed remotely using the 4G modem (requires SIM card).

    Engineer installing U-value measurement kit
    Data logger and heat flux plates installed
  3. Calculating and reporting U-values

    Once enough data has been collected, the data can be downloaded and used to calculate a U-value according to the ISO 9869 standard.

    The mean heat flux density is divided by the mean internal to external temperature difference to provide an average U-value over the measurement period.

    Conformity with the ISO 9869 standard will be determined based on the deviation in the R-value over each whole 24 hour period.

    U-value measurement on a computer